Adventure Time and Regular Show Xover Extravaganza!
by ITM
Summary: If you think you've read great Adventure Time and Regular Show Crossovers, you ain't seen nothing yet! Enter the Multiverse to do battle with an ancient evil known as Kanzargon. Watch the cast of AT and RS fight this evil to save their worlds. This story includes epic battles, a little romance, more epic battles, and friendship. (Mostly epic battles!) 10 Chapters! Part 1!
1. Chapter 1: Ice King's At It Again!

**Adventure Time and Regular Show Xover Extravaganza!**

**By: ITM**

_(Note: I don't own AT or RS, I'm just sharing my writing talents with the website.)_

**Chapter 1: Ice King's At It Again!**

_ In the world we live in, there are planets, galaxies, and as far as we know, only one universe. What if I told you that there is much more to the world? More planets, more galaxies, MORE universes! To be precise, more dimensions. I am Alahrah, the Lord of Dimensions. I am in need of desperate help! My brother, Kanzargon, the Lord of Space, wants to take over the multiverse! The only way to stop him is to gather the 10 "Heroes of the Prophecy". The Prophecy states that 10 heroes from two different dimensions in the Multiverse have the combined strength to stop Kanzargon. I must now go to one of the two dimensions to retrieve the first five Heroes. Until next time..._

**We now shift over to the Land of Ooo, where, as usual, the Ice King is up to no good, and our two heroes, Finn and Jake, try to stop him.**

"Ice King!" Finn yelled as he was running to catch the wizard of ice. "Hand over our treasure you stole!"

"Yeah!" Jake yelled as he was running on all fours alongside Finn to catch up with the Ice King. "Or we'll kick your fat butt!"

"I didn't steal it!" Ice King yelled back to Finn and Jake as he was flying with his white beard, while also holding on to a sack of gold and jewels. "I'm just borrowing it so I can afford a new weight-lifting set. I want to look good for the babes! Once I buy it, I'll pay you back!"

"No, WE'LL pay you back," Finn yelled. "With the beating of a lifetime!"

Jake threw Finn at Ice King, but missed.

"Hahaha!" Ice King laughed. "You missed!"

"Yes," Finn said. "But that was a distraction! Now, Jake!"

Suddenly, Ice King turned around to see a giant Jake use a giant fist to punch Ice King across the Grasslands, while at the same time, Finn used his acrobatic skills to land on both feet when he fell. Ice King landed in the snow of the Ice Kingdom, still holding on to the bag of stolen (borrowed) treasure.

"Haha!" Ice King laughed. "Grip of steel, baby! I learned after kidnapping so many princesses!"

Ice King then flew to his castle, entered through the window, and hid in his bathroom, quietly giggling that he outran (or in this case, outflew) Finn and Jake for the first time.

Finn and Jake were hot on the Ice King's trail. They weren't about to let Ice King get away with this villainous act of villainy. They entered the Ice Kingdom, ran up to the Ice Castle, and Jake stretched up to the top with Finn on his back. They entered through the window.

"Alright, Ice King," Finn said. "Come out and fight!"

"Why fight when my Icepede can laser-blast you into submission!" Ice King's voice echoed throughout the castle.

Suddenly, an Icepede bursted through an ice wall and started shooting lasers everywhere. Finn and Jake tried their best to dodge the frenzied laser blasts, but just weren't fast enough. Finn and Jake were repeatedly shocked from the lasers.

"You're lucky that my Icepede's lasers are set to 'shock', otherwise you'd be dead right now!" Ice King's voice cackled.

"Argh!" Finn yelled as yet another laser hit him.

Jake tried to make holes in his body so the lasers would go through the holes, but the lasers were too unpredictable to calculate a way to dodge them.

"This...is...bunk!" Jake yelled as he fainted from laser shocks.

Finn tried his best to not faint, but he just couldn't take this many lasers, so he followed suit with Jake.

* * *

Finn and Jake awoke to find themselves lying in their beds in their Tree Fort.

"What happened?" Finn asked.

"I don't know," Jake replied. "All I know is that I keep feeling this jolt every five seconds." ZZZZTTT! "OW!"

"Jolt," Finn muttered. "Jolt! We were jolted by the Ice King! He stole our treasure!"

"Wait," Jake said. "If he had us right where he wanted him, why didn't he finish us off, or put us somewhere where we can't kick his butt anymore? It doesn't make any sense."

"I agree," Finn said. "But we can't let him get away with this!"

Jake gasped. "Look! On the tree branch! It's a note!"

Jake was right. Finn turned around and saw a note on the tree branch. Finn got up, walked over to the branch, took the note off it, and read it aloud.

"Haha!" Finn read. "I have successfully beaten you dudes! By the time you read this, I've already used the money I borrowed to buy the new weight-lifting set!"

Jake gasped again. "That dishrag!"

"Don't worry, bros," Finn continued. "I put the money I owe you under Finn's bed, after I placed you here after my Icepede finished lasering you guys. Thanks again! Love, the Ice King (AKA, the _coolest_ king ever! See what I did there?")

"Aw man," Jake whined. "He beat us! Well, at least we got money back!"

Jake used his powers to stretch his arm towards Finn's bed, grabbed the bag of money from under it, and placed it on a dresser.

"Don't take his money!" Finn said angrily.

"Why not?" Jake asked. "He payed us back. What's the big deal?"

"It's the principle!" Finn explained. "He can't just take our money without asking and get away with it! He needs a butt-kicking!"

"OK," Jake agreed. "But how in the name of Gob are we going to get it back? He already spent the money, and that guy could've spent the money, and that guy could've spent the money! For all we know, some psycho could've melted our money and turned it into a golden cowboy hat!"

"Jake," Finn said. "Have you been eating pills from my medicine cabinet again?"

"They taste like candy," Jake moaned.

"We'll just bust into Ice King's castle, beat him up a bit, and leave."

"Isn't that breaking and entering, and assault and battery?"

"He deserves it!"

"Welp, that's good enough for me! Let's go manhandle his banandles!"

"Yeah!"

Jake got up, and did a fist pound with Finn.

* * *

Meanwhile, a dark entity is watching an orb showing Finn and Jake fist pounding.

"Ah yes," the entity said menacingly. "Two of the 10 Heroes of the Prophecy. The sooner they're dead, the better."

The dark entity waved his shadowy hand, and out of it dropped a little, dark sphere. Suddenly, the sphere started to mutate, growing arms, legs, a head, a torso, (in short, growing) until the sphere had gone from a sphere to an entity of shadow. The entity looked like a normal man, except it was all darkness, except for a mouth, and two red eyes.

"I am your creator, Kanzargon," the Lord of Space said. "You will be known as Nograznak. Your only purpose is to kill these two Heroes on the orb. If anyone stands in your way, kill them. Am I clear?'

"Yes, master." said Nograznak.

Nograznak then quickly dissapeared into thin air, leaving a haze of purple smoke behind. As soon as Nograznak left, Kanzargon began to chuckle.

"As soon as Nograznak is finished with those two fools, I'll move on to the remaining eight."


	2. Chapter 2: Nograznak Appears!

**Adventure Time and Regular Show Xover Extravaganza!**

**By: ITM**

_(Note: I don't own AT or RS, I'm just sharing my writing talents with the website.)_

**Chapter 2: Nograznak Appears!**

Finn and Jake rush over to the Ice Kingdom to teach the Ice King a lesson.

"Get ready for a butt-kicking, Ice King!" Finn and Jake yelled.

What the two didn't know was that they weren't going to kick Ice King's butt. THEY were the ones due for a butt-kicking.

* * *

Meanwhile, the evil (or crazy, take your pick) Ice King was working out with his new weights.

"Oh yeah," he said. "When the princesses see me, they'll fight each other to the death over me!"

Suddenly, Ice King heard an explosion of some sort. He flew over to his window and saw Finn and Jake running towards the Ice Kingdom.

"NO!" Ice King yelled. "I won't let them ruin my new masculine physique! Icepede, attack those two!"

Ice King waited for a minute and said: "Icepede! Where are you? Icepede!"

Ice King decided to search for his Icepede. He flew down several flights of ice stairs, and then found his beloved Icepede broken into peices.

"NNNOOOOOOOOOOOOOOOOOOO!" Ice King yelled in despair. "Who did this?! Was it you, Gunter! Gunter! Come out here right now! Gunter!

"No 'Gunter' here," an evil voice said. "Just you and me."

Ice King frantically looked around to find the mystery voice.

"Come out here right now, whoever-you-are," Ice King said. "And face the king of ice!"

"Actually, I'm not here for you," the voice said. "I'm here for Finn and Jake."

"How do you know our names?" Finn asked.

Finn and Jake were standing on the ice stairs, and were listening to the conversation the whole time.

"You two!" Ice King yelled. "Did you kill my Icepede?"

"What? No," Jake said. "We just got here."

"It was me." the voice said.

"Then you will die!" Ice King yelled, and started using his powers to shoot ice lightning everywhere, in an attempt to flush out the mystery voice.

Suddenly, a dark figure whooshed down from out of nowhere and attacked the Ice King. Ice King screamed in terror. The figure pushed Ice King to the ground, and started laughing. Finn and Jake knew that voice. It was Marceline the Vampire Queen.

"Marcy," Finn said walking up to her with Jake at his side. "Why are you here?"

"I got bored," Marceline said. "And I haven't messed with Simon in a while, and one thing lead to another."

(Author's Note: Admit it: you thought the mystery voice was Nograznak.)

Ice King stopped crying on the ice floor, looked up, and saw Marceline.

"Marceline," Ice King said. "YOU killed my Icepede?"

"The dumb thing shot at me, and I wasn't about to let it get away with that. It's the principle.

_"Thank you." Finn said in his head._

"Well, you didn't have to kill it," Ice King whined. "You could've just bonked it on the head."

Just then, another explosion occured.

"What the jug was that?!" Jake said, frightened.

"It came from downstairs, come on!" Ice King said as he lead the human, the dog, and the vampire queen down a set of ice stairs. When the four of them reached the bottom, they discovered yet another dead Icepede.

"NNNOOOOOOOOOOOOOOOOOOOOOOOOO OO!" Ice King yelled in despair again. "WHY MARCELINE? WHY WOULD YOU KILL ANOTHER ONE?"

"That...wasn't me, guys." Marceline stated.

"If it wasn't you, then who was it?" Finn asked.

"It was me." Suddenly, another dark figure appeared. It was all darkness, except for a mouth and two red eyes.

"Then, as stated before, you will die!" Ice King yelled as he shot ice lightning at the entity of darkness. It dodged easily.

"My name is Nograznak," the entity said. "And I want Finn and Jake dead!"

Before Finn or Jake could ask how it knew their names, Nograznak rushed towards Finn and Jake at blinding speed, and knocked both of them to the ground.

"Hey," Marceline said in anger. "Nobody hurts those two weenies except me!"

Marceline then transformed into her giant bat-monster form and advances towards Nograznak. The entity swiftly dodged a thrown fist by Marceline. The vampire queen then picked a chunk of ice leftover from a dead Icepede, and threw at Nograznak. Nograznak jumped over the ice chunk, and then flew towards Marceline. Upon reaching Marceline's face, Nograznak delivered a fury of punches to her face. However, Ice King blasted Nograznak with his ice magic, freezing the entity in a block of ice.

"Haha!" Ice King laughed, and then started singing: "I saved the day! I saved the day!"

Just then, Nograznak's frozen prison started to shake and vibrate, and rattle a lot, until it exploded, sending peices of ice in every direction. Marceline shielded herself from the incoming ice, but Ice King was hit square in the face, knocking him out. Nograznak then proceeded towards Finn and Jake, but Marceline stood in his way, holding her arms out.

"If you want those weenies so badly, you're gonna have to go through me, first!" Marceline said with a stern tone. She meant business. Nobody hurts her friends and gets away with it!

Nograznak remembers his orders when he was born:

_"Your only purpose is to kill the two heroes on the orb. If anyone gets in your way, kill them." Kanzargon had told him._

"You had your chance to run away," Nograznak said. "But you didn't. Now you will die."

As soon as Nograznak had finished his sentence, he rushed Marceline. He delivered a wave of punches and kicks to her chest, and then performed an uppercut to her face. Marceline fell backwards with a big thud.

"Ow!" Marceline yelled in pain.

Nograznak then reached into his chest, and then pulled out a sword made of darkness. He raised it just above the vampire queen's heart.

"Die!" Nograznak yelled.

Just then, a giant orange fist smashed Nograznak into the ground. Marceline looked up and saw Finn on the back of a giant Jake.

"Shmowzow!" Finn yelled. "This guy is insane!"

"Yeah," Jake agreed. "But now he's a pancake!" Jake started laughing. Finn couldn't help but laugh along with him.

However, a dark liquid was seeping out of Jake's giant fist. The liquid then began to collide with itself to make a body, which made Nograznak reappear. The entity pulled out his shadow sword from his chest again. Nograznak then settled in a battle stance.

"I got this!" Finn said assuringly. He jumped down from Jake's back and pulled out his father's Demon Blood Sword from his green backpack. He raised it in a battle stance as well. Jake then shrunk back to normal size.

"Your time is up, fool!" Nograznak screamed as he ran towards Finn. They clashed swords. Finn swung his sword horizontally, but Nograznak ducked and sweeped Finn's legs with his own. He then grabbed Finn by his blue shirt, picked him up, and threw him across the room. He collided with the ice wall, and fell to the ice floor. Nograznak then rushed towards Finn raising his sword in the air, jumped, and tried to slice Finn in half, but Finn rolled out of the way and did a somersault to get back to his feet.

"You're tough, aren't ya?" Finn said with a smile.

Nograznak didn't take that compliment nicely. He ran towards Finn and swung his sword, but Finn blocked the attack. The two then continued to clash swords for a while until Finn jumped over Nograznak, and sliced him in half. Both dark halves of his body fell to the floor.

"Slammacow!" Finn said in a happy tone. "That was awesome! I never had a good fight like that in weeks!"

"Yeah!" Jake said. "You showed him who's boss!" The two bros then pounded fists.

"Wait a minute," Marceline said with a worried tone. "How is it that I couldn't beat him, but you could?"

"What can I say?" Finn said with a cocky voice. "I'm the man!"

Marceline rolled her eyes. "Guess I'm just getting rusty," she said as she turned back into her normal form.

Suddenly, the two halves of Nograznak both let out an arm made out of darkness, and the two arms connected with each other, and pulled Nograznak's body back together.

"Aw, come on!" Jake complained. "Is there no stopping this guy?"

"Don't worry!" Finn said assuringly. "I'll cut him into peices!"

Finn ran towards Nograznak and swung his sword horizontally, but Nograznak blocked it. Finn, Jake, and Marceline gasped at what they just saw. Nograznak didn't block the attack with his sword, he blocked it with his hand. He caught the blade of Finn's sword right between two of his shadowy fingers. Finn tried to pull the sword away, but Nograznak had a strong grip with his fingers, so the sword wouldn't budge.

"This is your end," Nograznak said in a dark voice. "Prepare to die."

Nograznak punched Finn in the stomach with his free hand, which brought Finn to his knees, causing him to let go of his sword.

"Finn!" Jake yelled. He rushed towards Finn to help him, only to get sent flying with a big kick to the face by Nograznak.

"Don't worry, Nograznak said in a menacing voice. 'You'll see him again...in the afterlife!"

Nograznak was then punched in the face by Marceline, who snuck up behind the entity with her invisibility powers when Jake was distracting him. Marceline had a smile on her face, but it quickly dissappeared when she saw that Nograznak was unphased by the attack. He then grabbed her, and threw her across the room. She was thrown so hard she didn't just collide with the ice wall, she was sent crashing threw it. Marceline moaned in pain, and then fainted.

"You'll get your turn," said Nograznak. "But first I'm going to crush Finn's skull under my foot!"

Nograznak then raised his foot right above Finn's head, and brought it down.


	3. Chapter 3: Why Me?

**Adventure Time and Regular Show Xover Extravaganza!**

**By: ITM**

_(Note: I don't own AT or RS, I'm just sharing my writing talents with the website.)_

**Chapter 3: Why Me?!**

Nograznak brought his foot down upon Finn's skull, or was about to. Something was holding his foot up, a long, orange arm. Nograznak looked to his side and saw that Jake had stretched his arm towards Nograznak and was holding his foot up with his hand. Jake then stretched his other arm towards Nograznak and punched him in the face. However, Nograznak was unphased. He grabbed both of Jake's arms, and threw Jake at a wall.

"Don't intervene," Nograznak said.

He then lifted his foot up to try to smash Finn's skull again, but saw that Finn was no longer there. He also noticed that he was no longer holding Finn's Demon Blood Sword in his fingers. He dropped the sword when he grabbed Jake's arms. Then, it hit Nograznak: that was a distraction. Just at that moment of realization, Finn used his sword to slice Nograznak into several pieces. After those pieces fell to the ground, Finn ran over to Jake, and tried to help his bro.

"Thanks, Jake," Finn began. "You saved my butt back there, or rather my head."

"Haha," Jake laughed. It was a weak laugh. "No problem, dude. Homies help homies."

"You're really jacked up, though," Finn stated.

"No worries," Jake said. "I'll survive."

"But you've been knocked to the floor, kicked in the face, and now smacked into a wall."

"I've been through worse."

"I don't wanna see you die, man."

'Then let's get outta here, bro."

"That's not happening," a voice said. It was Nograznak. While Finn and Jake were talking, Nograznak's body was being reformed.

"Aw, dingle!" Finn said.

Nograznak pulled out his shadow sword from his chest. Finn then readied his Demon Blood Sword. The two ran towards each other, and clashed swords. Finn swung wildly and missed. Nograznak kicked Finn in the jaw, causing him to fall to the ground.

"Now I have you right where I want you," Nograznak said in a sinister voice as he raised his sword, ready to strike Finn down.

"That's what you think!" Jake yelled as he grew big and smashed Nograznak into the ground with a big fist. Once again, a dark liquid seeped out of Jake's hand, and reformed Nograznak's body.

"If you want to die so badly," Nograznak said. "Be my guest."

Suddenly, to Jake's horror, Nograznak started to grow. His shadowy body started to extend itself, causing Nograznak to expand in size. Jake stared in terror as the entity was up to Jake's size. Nograznak punched Jake in the face, which caused him to cover his face with his hands. Nograznak then swept both of Jake's legs, and he fell to the floor. Nograznak's giant shadow sword was in his hands, ready to strike Jake down this time. However, Nograznak felt a sudden pain in his ankle. He looked down and saw Finn stabbing Nograznak's ankle with his Demon Blood Sword.

"When will you ever learn?" Nograznak asked in a sarcastic voice. "I cannot be beaten. I am the spawn of a god!"

"What?!" Finn yelled in terror and confusion. "You're a...a...a..."

"Demigod," Nograznak said. "Half mortal, half god. I am the spawn of the god known as Kanzargon, the Lord of Space. He has created me for the sole purpose of annihilating you two."

"What?!" Finn said. "Why me?! And Jake?!"

"I do not know," Nograznak said. "I was created for that reason. I have no other purpose."

"So you're just gonna blindly follow your dad?"

"It is not 'blindly following,' it is doing what I was created to do."

"So you're just a puppet!"

"I am no puppet! I am a demigod! I am second in power only to my creator. Once you two are dead, I will have fulfilled my purpose, and return to being my creator's aura."

"His what?"

"Aura. I am a piece of the Lord of Space's aura, his energy, his lifeforce. Once I kill you two, Kanzargon will absorb me, and turn me back into his aura."

"Wait! It doesn't have to be like this! You can find another purpose, one that doesn't involve skebopping dudes."

"No."

Nograznak was done talking. Unbeknownst to Nograznak, so was Finn.

"Now, Jake!" Finn yelled.

Just then, a gigantic Jake wrapped around the giant demigod. Jake began squeezing tightly, and began turning Nograznak into dark liquid. The liquid escaped Jake's grasp and reformed itself to be Nograznak's body.

"You won't be able to fight both of us at the same time!" Jake said confidently.

"We'll see," Nograznak said. "Nice try distracting me, though. However, that's not going to work from now on."

"We'll see," said both Finn and Jake.

Nograznak shrunk back to his normal size, and so did Jake. The three of them then started what might be one of the greatest two-on-one fights ever. Finn swung his sword at Nograznak, but missed. Jake then threw a punch at the demigod, but also missed. Nograznak tried to punch Finn in the stomach again, but Finn jumped out of the way. Nograznak then tried to kick Jake in the face, but Jake shrunk down, causing him to miss, and then grew back to normal size.

"This is much better," Nograznak said with an evil smile. "But you will still never defeat me."

Finn threw two punches with both of his hands, but Nograznak grabbed them both, and threw Finn at a wall. However, Jake smashed the demigod between two giant fists, grabbed him, and then threw HIM at a wall. However, Nograznak landed feet-first on the wall, then wall-kicked to land on his feet. Nograznak was only a few feet away from Finn, who was still lying on the floor. Nograznak pulled out his shadow sword from his chest again and tried to strike Finn, but Finn blocked it with his sword. Finn then got up, and began clashing swords with the demigod again. While the two were sword-fighting, Jake was thinking of a plan to beat Nograznak. He thought of all his skills: stretching, swordplay, and reforming his body. how can he use those against him? Suddenly, something in Jake's brain clicked. What if the demigod was cut with HIS sword? Would he reform? It was their only plan, so it was worth a try. Meanwhile, Finn and Nograznak were still sword-fighting. no one seemed to have the upper hand, until Nograznak punched Finn in the face, knocking him to the ice floor. Jake then saw this as his golden opportunity. He stretched his arm at Nograznak's arm with the hand holding the sword, and managed to swipe the demigod's shadow sword.

"I guess it's you that wants to die first," Nograznak said with an evil tone.

Nograznak rushed towards Jake. Jake then swung the shadow sword, and sliced Nograznak in half. Jake then sighed in relief.

_"I did it!" Jake thought. "I beat him! I mashed his potatoes!"_

Suddenly, Nograznak reformed his body.

"You've got to be kidding me!" Jake yelled.

The demigod punched Jake in the face, sending him flying at a wall.

"No more games," Nograznak said in a serious voice. "You die now!"

Nograznak flew towards Jake and started to beat him to death. He delivered a flurry of punches and kicks to the magic dog. Jake was then grabbed by the neck, taken high into the air, and finally thrown down to the floor. Jake started to cough up blood.

"No one can save you now," Nograznak said.

Just then, the demigod turned around to see Finn running towards him, sword ready to slice. Nograznak kicked Finn in the jaw once more, causing him to bleed as well.

"Like I said," Nograznak continued. "No one can save you now. But, just to be safe..."

Nograznak flew towards Ice King's limp body, and threw it out the castle entrance, landing hard on the ground. The same happened to Marceline's limp body. Nograznak then walked over to Finn's body. He picked him up, and threw him through another ice wall, sending him crashing through the wall. Suddenly, the castle started shaking. Nograznak realized that because the room was down two walls, it was going to fall apart. This gave the demigod an idea. Nograznak flew out of the castle, leaving Finn and Jake to be buried under tons of ice. Finally, the castle fell apart. It caved in on itself, and all that was left was giant piles of ice. Nograznak then smiled.

"Hahahahahahaha!" Nograznak laughed. "That was harder than I thought, but I did it! Now to return to Kanzargon."

Nograznak then dissappeared, leaving behind purple smoke.

Just then, the purple smoke filled Marceline's nostrils. She finally came to, and started coughing.

"What happened?" Marceline asked. She looked around, and saw that the ice castle was in pieces. "Where is Nograznak?" She continued to look around and then, something clicked in her mind. "Where's Finn and Jake?!"

Marceline's scream awoke Ice King.

"What happened?" Ice King asked, rubbing his head.

"That weird thing dissappeared, and so did Finn and Jake!" Marceline said, tears forming in her eyes.

"Wait a minute," said Ice King, looking at his castle, or what was left of it. "WHAT HAPPENED TO MY CASTLE?!" he screamed.

"That guy must've destroyed it, and left," Marceline stated.

"My castle is ruined!" Ice King said. He then started to cry. "Why me?!"

"Forget that, where's Finn and Jake?"

"I don't know. I'll try to lift the ice."

Ice King used his ice powers to lift the ice up from the ground, and move it to the side. What Ice King and Marceline saw was horrifying. Finn and Jake were lying under the rubble limp, with bones coming out of their bodies. Blood was caked on their bodies. They were dead.

"No," Marceline said quietly. "No!" Marceline was getting louder. "NNNOOOOOOOOOOOOOOOOOOOOOO!"


	4. Chapter 4: Regular? I Think Not!

**Adventure Time and Regular Show Xover Extravaganza!**

**By: ITM**

_(Note: I don't own AT or RS, I'm just sharing my writing talents with the website.)_

**Chapter 4: Regular? I Think Not!**

_"Oh, no! Two of the 10 Heroes Of The Prophecy have died at the hands of one of Kanzargon's soldiers. He'll do whatever it takes to make sure he'll rule the Multiverse. However, I know of a way to get the Heroes back. But, if I leave to do this plan, two other Heroes will be in danger. But I, Alahrah, must travel to the Underworld to set free the fallen heroes. I only hope that the blue jay and raccoon survive Kanzargon's onslaught."_

**Now, we shift over to the Park, where our two favorite groundskeepers are up to no good.**

"MORDECAI! RIGBY! WHAT HAVE YOU DONE?!" Benson yelled in a VERY angry voice.

Mordecai and Rigby ran up to Benson.

"What is it, Benson?" Mordecai and Rigby asked their angry gumball machine boss.

"Did you do this?" Benson asked as he pointed at the fountain. The water in it was all brown.

"We did an experiment," Rigby answered. "We wanted to see if a person could swim in soda. And they totally can!" Rigby raised his hand to high-five Mordecai, but the blue jay didn't raise his.

"Look, we're sorry, Benson," Mordecai said. "We'll clean this mess up."

"No you won't," Benson said. "Because you're both fired!"

"WHAT?!" Mordecai and Rigby said.

"You've done too much to this park," Benson said. "And if we were to keep you two around any longer, the Park would go bankrupt!"

"Oh, come on!" Rigby complained. "The Park wouldn't go _bankrupt._"

"You know what?" Benson asked. "I DON'T CARE! YOU'RE BOTH FIRED, SO GET THE STUFF IN YOUR ROOM, AND GET OUT!" Benson then stormed off.

* * *

Meanwhile, Kanzargon was watching his creation beat up Finn and Jake on his orb. The Lord of Space was loving every minute of this little show. Finally, he applauded when he saw Ice King and Marceline look at Finn and Jake's torn up, broken, dead bodies. Suddenly, an explosion of purple smoke appeared, and behind the smoke was Nograznak.

"Well done," said Kanzargon. "You couldn't have done a better job."

"Thank you, creator," said Nograznak. "Since I have vanquished those two, I am ready to become your aura again."

"Actually," said Kanzargon. "You've done such a good job killing Finn and Jake, I'm going to give you another job!"

"Really?" Nograznak asked.

"Sure! I want you to go into a new dimension, and kill two more Heroes. Again, if anyone gets in your way, kill them."

"Yes, creator. "Who shall I kill?"

Kanzargon rubbed his orb, and Mordecai and Rigby appeared on it, collecting their things from their room.

"These two," said Kanzargon with a sinister voice. Nograznak looked at the orb, and frowned.

"Creator," Nograznak began. "Not to object, but those two don't look like a challenge."

"They don't have to be a challenge, they have to be dead! Now do as you're commanded!"

"Yes, creator." Nograznak then disappeared, leaving behind purple haze.

* * *

Back at the Park, Mordecai and Rigby had just finished putting away all their stuff in their suitcases. Mordecai was giving Rigby the cold shoulder.

"Come on, Mordecai," Rigby whined, "Why won't you talk to me?"

Mordecai turned around and punched Rigby in the gut. The raccoon fell to the floor, moaning in pain.

"Don't ever talk to me again!" Mordecai yelled. "I am sick and tired of hearing your crap! It's you that got us fired! You said: 'Hey, Mordecai! Let's fill the fountain with soda and swim in it!' Oh, and this is the best part: I DIDN'T FILL THE FOUNTAIN WITH SODA! YOU DID! You got me fired along with you, and I didn't do jack! You are worthless, you know that! The only good you're for is making people's lives suck! Now get out of my sight!" Mordecai left Rigby there on the floor in pain. Rigby then started to cry. He wanted to tell Mordecai he was sorry.

Suddenly, Rigby heard an explosion outside. He got up, looked out the window, and saw purple smoke in front of Mordecai. The blue jay dropped his suitcase, and stumbled backwards to the ground. Rigby then gasped at what he saw: an entity of darkness that was shaped like a man, except it was ALL darkness, except for a mouth and two red eyes. Rigby dropped his suitcase, ran outside, and saw the entity beat upon Mordecai. The entity punched and kicked Mordecai in the face, causing the blue jay to bleed. The entity then reached into his chest, and pulled out a sword made of darkness. It raised the sword above Mordecai's chest, about to strike.

"Die!" said the entity.

"NOOOOOO!" Rigby yelled as he ran towards the entity on all fours. He pushed the entity out of the way, causing it to drop its sword, landing right on Rigby's back. Rigby screamed in pain. Blood quickly began rushing down his back.

"Holy crap!" Mordecai yelled. He got up and knelt beside Rigby. "What were you thinking?!"

"I was thinking of saving your life," Rigby said in a very weak voice. "Which I did. Oooooo-" Rigby then started coughing up blood.

"Rigby!" Mordecai yelled. "I can remove the sword from your back!"

"I think it's too late for that. It won't stop the blood."

"Rigby! Why did you do this?! After what I said to you!"

"Easy: you're my best friend, like a brother to me. You've always have been. I know we say a lot of stuff to each other, and you probably meant what you said to me, but know that you've always be my bro, no matter what. You're a good friend, Mordecai."

Mordecai picked up Rigby and held him in his arms. "No! Rigby! Please don't die!"

"Sorry, Mordecai. But, know that I always care for you, now matter...what...I...say..." Rigby then closed his eyes. Mordecai checked his pulse. There wasn't one.

"No!" Mordecai yelled. "NO! NOOOOOOOOOOOOOOOOOOO!" Mordecai started to cry. He hated himself for being a jerk to Rigby, and never apologized for it, not even right before he died. "Rigby, you always were my best friend. I couldn't ask for a better one. You were like a brother to me as well. I loved you like a brother. And now, your dead. You died saving my life. You didn't deserve this fate, Rigby! I deserved it for being a jerk!" Mordecai then eyed the sword in Rigby's dead body. He removed it, and observed it. The sword was covered in Rigby's blood. Mordecai gritted his teeth, and was seething with rage. He looked at the entity and scowled.

"This is all your fault!" Mordecai yelled. The blue jay then ran towards the entity, sword raised in the air. He screamed in rage as he sliced the entity in half. The two pieces fell to the ground. Mordecai breathed hard, and dropped the sword.

_"I did it, Rigby," Mordecai thought. "I avenged your death."_

Suddenly, the entity's halves grew dark arms that connected with each other, and pulled the entity back together. Mordecai watched in horror as the entity got up, and picked up the shadow sword.

"You are going to regret that," the entity said. "In the afterlife!"

In blinding speed, the entity rushed towards Mordecai and before he could react, the entity stabbed Mordecai in the chest. Blood quickly poured out of the hole in Mordecai's chest. Mordecai was fading fast, but he knew he couldn't let Rigby down. He used the last of his strength to punch the entity in the face. However, the entity was unphased.

"Who...who...are...you?" Mordecai said weakly.

"Your end!" said the entity.

Mordecai just couldn't take it anymore, and faded away into the Underworld. The entity tossed Mordecai's dead body aside.

"That was boring," it said. "Not even a challenge. That pathetic ice wizard put up a better fight than these two combined! I'm leaving this dimension."

The entity disappeared in a haze of purple smoke.

Just then, Benson was walking outside and saw something that made him throw up. Mordecai and Rigby's bodies were bloody and torn. "Holy crap!" he screamed. "Someone call 911! There's some psycho on the loose!"

* * *

Meanwhile, Kanzargon was watching Nograznak beat the life out of Mordecai and Rigby on his orb. He laughed when he saw the pathetic attempt of Mordecai slicing Nograznak in half to avenge Rigby. Nograznak then appeared behind Kanzargon in his trademark entrance: purple smoke explosion.

"The job was successful," Nograznak said.

"I saw," said Kanzargon. "Very successful. I am very grateful for your service."

"So I shall go back to being a part of your aura?" Nograznak asked.

"Yes." Kanzargon then placed his shadowy hand upon Nograznak's shoulder, and absorbed him through his hand. Kanzargon felt a surge of power through his body. He then rubbed the orb, which then revealed another Hero of the Prophecy. "What is that thing? A robot? How can that be a Hero of the Prophecy? I guess it doesn't matter. I won't need Nograznak for this petit fool. I shall hire a mercenary to hunt it down and destroy it!" Kanzargon then opened a portal with his hand, and went through it.


	5. Chapter 5: Meeting In The Afterlife

**Adventure Time and Regular Show Xover Extravaganza!**

**By: ITM**

_(Note: I don't own AT or RS, I'm just sharing my writing talents with the website.)_

**Chapter 5: Meeting In The Afterlife**

**We now enter the land of the dead, where all dead spirits go, regardless of the dimension. (Hint, hint.)**

"Uhhh," moaned Finn. "Where am I?" Finn got up from the ground. He was sleeping (unconcious) on the ground.

Finn looked at his surroundings. He gasped at what he saw. The ground was grey, the skies were black, there were skeletons and ghosts all around. The worst part was that Finn knew this place. Finn was in the Underworld: where all dead spirits go.

_"This could only mean two things," Finn thought. "Either I got drunk on ice cream again and accidently opened a portal to the Underworld, or worse..."_

Finn looked at his body and tried to put his arm through his chest. He did.

_"Oh, skiz!" Finn thought. "I'm dead! I'm a spirit!"_

Just then, Finn heard a moan nearby. Finn used his new spirit body to fly towards it. When Finn located the moaning sound, he saw it was some sort of raccoon. Of course, it was the spirit of a raccoon. Finn nudged it little with his spirit foot.

(Author's Note: Spirits can touch other spirits. They don't go right through each other.)

The raccoon spirit flailed his arms in a way to shoo Finn's legs away.

"No, no," said the raccoon spirit. He was talking in his sleep. "Don't kill him! You weird shadow guy!"

Finn gasped when he heard this for two reasons: 1. It was a talking raccoon. 2. It couldn't have been a coincedence that this raccoon must've suffered a similar fate as he and Jake did to the demigod known as Nograznak. Then again, Finn thought the raccoon might've been a crazy, sociopath. Finn decided to pick up the raccoon spirit, and shake it awake. Finn began to shake the raccoon spirit awake.

"Hey, dude," Finn said. "Wake up. I need to ask you some things."

The raccoon started to open his eyes, and when he a human, spirit, thing holding him, he started to scratch Finn's face.

"Don't touch me, you freak!" the raccoon spirit yelled.

Finn dropped the raccoon spirit and covered his face.

"What the slug, man?!" Finn yelled. "Why did you do that?!"

The raccoon spirit stood up and started breathing heavily.

"You were trying to do something to me!" the raccoon spirit responded. " For all I knew, I thought maybe you were trying to mug me!"

"Why would I mug a dead raccoon?!" Finn yelled.

"For your information," the raccoon began. "My name is Rigby! And I am not dea-, wait, would did you say I am?"

"Dead! You're a spirit in the Underworld, therefore you are dead!"

"I can't be dead! I just dreamt me and my friend getting fired from our jobs, ambushed by a shadow guy, me getting stabbed in the back, and who knows what happened to Mordecai!" Rigby gasped. "Mordecai! Where's Mordecai?"

"Who's Mordecai?"

"Mordecai is my best friend, and-, wait a minute, why am I telling you all this? You're just a kid."

"I don't know, I'm not a sociopath."

"Hey! No one calls my a sociopath!" Rigby ran towards Finn on all fours and attempted to tackle him, but Finn reversed it by stepping to the side, picking Rigby up, spinning him in the air once, and throwing him at the ground.

"Ow!" Rigby yelled. "Why'd and how'd you do that?"

"You tried to flippin' tackle me, and I am an excellent fighter!" Finn said in an annoyed voice. Finn then grabbed Rigby by the chest and held him close to his face. "Now listen carefully: you didn't dream nothin'. You're dead, and in the Underworld as a spirit. Now, I'm going to put you down, and when I do, I'm gonna ask you a question of vital importance. And you're gonna answer me truthfully, or else, understand?" Finn asked in an agressive tone while holding his fist in the air.

"Yes!" Rigby said in a scared, girly voice. Finn put Rigby down.

"Now, can you remember how you died?" Finn asked, trying to sound nicer and friendlier, like there was never any bad blood between them.

"Yes," Rigby said, in a scared, but calmer voice than before. "I died saving my best friend Mordecai."

"How exactly did you die?"

"Okay, you might not believe me, but there was this guy, that was made out of darkness, or something. He came out of nowhere and attacked my friend Mordecai. He was about to stab him with a sword, but I stopped him. However, the sword landed in my back. The last thing I remember is telling Mordecai...how much he means to me." Rigby then started crying. "I hope he's okay."

"This Mordecai dude, sounds really important to you. Is he your brother, or something?"

"He was like a brother to me, we were best friends. Now either he's dead, or he's being tortured by that monster."

"I know what that feels like. I was also killed by that barfsack named Nograznak."

Rigby snickered. "His name is Nograznak? That's the dumbest name I've ever heard."

"To me, now it's the scariest name I've ever heard. "Just thinking about it sends chills down my spine."

"Oh come on, he's not that scar-, whoa, whoa, whoa, back up a little, you said YOU were killed by Nograznak?"

"Yup. Myself, and my best friend Jake. He's my brother."

"Wow, so we actually have a lot in common. We both have best friends, and we both died at the hands of that jerk! Now we can never see the joys of life again!"

"Actually, this isn't my first time here."

"WHAT?! HOW CAN YOU DIE, COME BACK SOME HOW, THEN DIE AGAIN?"

"Whoa, keep your shirt on, dude. I never died until now. I long time ago, I accidently killed my friend's plant, then went here to retrieve its soul. I got it, left, met Nograznak, then he shipped me back down here the natural way."

"Wait, so if you came here and left, you must know the way out!"

"What's the point? We're both dead."

"Wait, hear me out, I've got a plan. You said you retrieved the soul of a dead plant, so maybe we can retrieve our dead souls! Then, when we're alive again, you can lead us to the exit, and we can leave this place!"

"It's...not that simple. To retrieve our souls, we'll have to get to Death's castle. Death is the only one who can return dead souls. Also, I don't know an exit. Death creates one."

"Then the plan is shortened! All we have to do is find Death, have him give us our souls back, then he can make us an exit!"

"Well, I guess it's worth a shot. We've got no other plan, so let's go for it!" Finn held out his hand, gesturing for Rigby to hit it with his fist. Rigby fist bumped with Finn. The two spirits then walked in a random direction.

"So," Rigby started. "Do you know where Death's castle is?"

Finn opened his mouth to say something, but his jaw dropped, and his mouth remained open. "No."

"We're lost?!"

"Yup."


	6. Chapter 6: Meanwhile In Ooo

**Adventure Time and Regular Show Xover Extravaganza!**

**By: ITM**

_(Note: I don't own AT or RS, I'm just sharing my writing talents with the website.)_

**Chapter 6: Meanwhile In Ooo**

**We now head back to the Land of Ooo, where every resident of the Candy Kingdom is in despair.**

In the Candy Kingdom, every denizen there was in tears. They were building a statue in memory of Finn the Human and Jake the Dog. Also, they were having their funeral there as well. Finn and Jake's dead bodies were loaded up in their respected coffins. Then when they reached the cemetery, they placed the coffins in a ditch and buried them. Once the coffins were buried, tombstones were placed on their graves. One said: R.I.P. Finn the Human: "Ooo's Greatest Hero." The other said: R.I.P. Jake the Dog: "Ooo's Greatest Sidekick." When all the Candy People left, only a few residents remained. Princess Bubble gum was crying over both graves.

"Oh, Finn and Jake," she cried. "I didn't want you to go this way!"

Lady Rainicorn was crying over Jake's grave.

(Author's Note: Since I don't know Korean, let alone know how to type it, I'm just gonna translate to make things easier.)

"Jake!" Lady cried. "I'm sorry! I don't know what to tell the kids!"

Flame Princess was crying burning tears over Finn's grave.

"Finn," she cried. "I always loved you! The moment I saw you! I'm sorry it took me this long to tell you!"

Ice King and Marceline were watching from a distance. Marceline was holding back tears, while Ice King was crying.

"My two best bros," he began. "Gone for eternity! Why, Glob?! Why take them in the name of evil?!"

"It wasn't Glob's fault," Marceline shouted at him, with tears now flowing down her cheeks. "It's Nograznak's! He killed Finn and Jake in the name of evil. We need to hunt him down, and kill him, to avenge Finn and Jake."

"Yeah!" Ice King agreed. "And my castle, too!"

"Count me in, too." said an angry voice. Ice King and Marceline turned around and saw Flame Princess, with her fists balled.

"I want to avenge Finn's death," she said. "I want to make whoever killed him pay."

"I want to come, too," said Princess Bubblegum. "And so does Lady." Lady Rainicorn was carrying Princess Bubblegum on her long back.

"Alright, then it's settled," Marceline said. "The five of us will hunt down Nograznak and kill him to avenge Finn and Jake's death."

"Peppermint Butler!" Bubblegum yelled. Peppermint Butler came running towards the princess of the Candy Kingdom.

"Yes?" Peppermint asked.

"In my absence," Bubblegum began. "You will be in charge of the Candy Kingdom."

"Very well," he said. Peppermint then left for the castle.

"Let's go!" Ice King yelled. He flapped his beard and started flying with it. Marceline used her powers to fly alongside Ice King. Flame Princess used her fire powers propel herself off the ground and into the air, then using her powers like how a rocket ship would use its engine to fly. Lady Rainicorn, still with Bubblegum on her back, flew with the rest of the group. Just like that, the five set out on a journey to find and kill Nograznak, a futile journey.

* * *

Meanwhile, still in Ooo, Beemo had just got back from Finn and Jake's funeral. Although he had heard that Ice King, Marceline, Flame Princess, Princess Bubblegum, and Lady Rainicorn would try to find Finn and Jake's murderer, he decided to stay at the Tree Fort. He thought that he would be of no use to the five. However, Beemo was still going to track down Finn and Jake's murderer, one way or another. Beemo then started another one of his "BMO Noire" mysteries.

"My two best friends," Beemo said to himself. "Are now dead. I know that the murderer's name is Nograznak, for I had overheard Ice King and Marceline's discussion, but as far as I know, there is no one in the Land of Ooo named Nograznak. It doesn't make any sense. So, I decided to check the records of every denizen in Ooo."

Beemo walked to the basement of the Tree Fort. He pushed aside a few drapes to reveal a secret teleporter he had hidden under the Tree Fort for extreme emergencies, and Beemo could think of no bigger emergency. Beemo punched in a few coordinates, and the teleporter then teleported Beemo to the Grand Meeting of Ooo Royalty place. Beemo landed in a room in the building. He then walked up to a door, and knocked on it in a code sort of way. The door was then opened by Emerald Princess, who had also just came back from Finn and Jake's funeral.

"Thanks, Emerald Princess," Beemo said in a casual voice. Beemo then walked away.

"You're welcome," said Emerald Princess. "But why did you knock in such a weird way? No one here works for you."

Beemo ignored the princess and walked towards a room that had a door that said: "Ooo Records."

"Bingo!" Beemo stated. He pushed opened the door and walked inside. The room was filled with filing cabinets, each with their own labels. Beemo saw and opened one close to the ground that said: "Denizens of Ooo Profiles: Letter N." He looked through the cabinet, and saw that "Nograznak" was nowhere in it.

"Just as I thought," Beemo said to himself. "Nograznak does not, or has ever, existed in the Land of Ooo. So, how did he get to Ooo, let alone, how does he know Finn and Jake. The two have never talked about him before. None of this is adding up. I guess this is one case that can't be solved."

Beemo decided to give up. He walked back to the secret teleporter and turned it on. He was then teleported back to the Tree Fort. Upon arrival to the Tree Fort, Beemo looked at the teleporter, as if that the machine had a secret that it was keeping from Beemo. All of a sudden, it hit Beemo.

"That's it!" Beemo yelled. "Nograznak is not from Ooo! He's from another world! He must've teleported from his world to get here, then killed Finn and Jake with currently unknown motives. Finally, the murderer teleported himself back to his world. It explains a lot! I must tell the five that their search is hopeless, or they might get into some real deep doo-doo trouble! But, I'm gonna need some help. And there's only one person I can go to for help!" Beemo ran down to the treasure room in the Tree Fort to recruit what would be Beemo's new partner.

* * *

Meanwhile, still in Ooo, Kanzargon had just transported himself to Ooo, where he then traveled to the secret location of the dreaded G.O.A., the Guild of Assassins. Kanzargon had been watching Finn and Jake's past adventures, and saw one little villain that was so good at fighting Finn and Jake, he decided to pay her a little visit. Kanzargon transformed himself into a man in dark robes holding an oak staff. He used his staff to knock on the door of the G.O.A. hut. A lizard-man opened the door, with a sword in hand.

"What do you want?" the lizard asked.

"I want to speak with an assassin named Me-Mow," Kanzargon requested.

The lizard nodded, and let Kanzargon in. The lizard led Kanzargon to a room that housed a little cat. The lizard walked away from Me-Mow and Kanzargon.

"How can I help you?" Me-Mow asked.

"I need you to assassinate someone for me," Kanzargon said. He then pulled out an orb from his robe and rubbed it. The orb showed Beemo walking in the Tree Fort. "This robot must be destroyed."

"Sure, I'll do it," Me-Mow agreed. "How much will you pay?"

Kanzargon put his orb back in his robe and pulled out a sack of gold.

"Deal," said Me-Mow after staring at the money. The cat grabbed her poison injector, but Kanzargon stopped her.

"You can't poison a robot," Kanzargon stated.

"You have any better ideas?" Me-Mow asked in an annoyed voice.

Kanzargon pulled out a dagger made of darkness, one small enough for Me-Mow. Kanzargon handed the dagger to Me-Mow. The tiny cat practiced using the dagger by giving it a few swings and stabs.

"Excellent," she said in a sinister voice. "The robot will be dead by tomarrow."

"Very well," Kanzargon said. "You better not fail me, or you'll be in deep water, my friend." Kanzargon left the G.O.A. hut. Me-Mow followed suit, and started making her way to the Tree Fort.

"Robot," she said to herself. "You're as good as dead!"

* * *

**Well, that about wraps up this chapter. We're almost done with the book! Just one thing, I seem to be in this "fanfiction feud" with this book called "OOO SOUTH HIGH SCHOOL." The author always seems to put up a new chapter every time I do. Now, I don't want to ruin that book or its author, but I really want to outdo it in popularity, so review, follow, and favorite! Chapter 7 will be out in no time! Until next time!**


	7. Chapter 7: Beemo VS Me-Mow

**Adventure Time and Regular Show Xover Extravaganza!**

**By: ITM**

_(Note: I don't own AT or RS, I'm just sharing my writing talents with the website.)_

**Chapter 7: Beemo VS Me-Mow**

Back at the Tree Fort, Beemo has finally made his way to the treasure room, where he found his new partner.

"Believe me," said Beemo. "You were not my #1 choice, but you are my only choice. The police can't help, this case is too big for them. So, are you with me?" Beemo extended his hand to his new partner.

"Okay!" NEPTR agreed, extending his claw to shake Beemo's hand. "But, how are the two of us going to solve this big mystery? And who's gonna guard the Tree Fort while we're gone?"

"Don't worry," Beemo said in an assuring voice. "The police can guard the Tree Fort, and we are gonna go to the five people who can assist us in this case."

"How can five people help us?" NEPTR asked.

"Ice King, Marceline, Flame Princess, Princess Bubblegum, and Lady Rainicorn are hunting down Nograznak as we speak, but what they don't know is that Nograznak is not of this Earth. He is some sort of alien or being from another world. If the five keep searching, it'll be a waste of time. We have to tell them they're not going to find anything."

"I still don't see how that is going to help us catch a perp from another world."

"I have a plan, but we're gonna need the five to do it. If the plan works, we might just have a shot at taking down Nograznak."

"Alright then! Let's go!"

"You're not going anywhere!" said a mysterious voice.

"Who's there?" Beemo asked.

Suddenly, a figure (a very small figure) dropped from the ceiling. It landed on the wooden floor. It was a tiny cat.

"Who are you?" NEPTR asked.

"Me-Mow," the cat answered. "Assassin, second class. I've been hired to kill you!"

Beemo started to laugh. "_You _kill _us_?" he asked in a mocking voice. "We're both twice your size! You couldn't possibly harm us!"

Me-Mow scowled. "I'll have you both know that I'm one of the greatest assassins to have ever lived!" she yelled at them.

"Sure you are," NEPTR mocked. "Greatest of all assassins under one foot!"

"Oh," Me-Mow began, as she started develop an evil smile. "You'll see. You'll see just how dangerous I am!"

Me-Mow pulled a tiny, yellow dagger out of her mouth. She then rushed Beemo, climbed him, got to the top of his head, and tried to stab Beemo with her dagger, but the dagger broke on contact.

"Wow," Beemo stated. "That dagger sucks."

"Tell me about it," she muttered. Beemo grabbed Me-Mow, and threw her aside.

"Leave now!" Beemo said in a stern voice. "Before we call the police, who ironically are cats!"

"The police have never caught me!" Me-Mow exclaimed. "Never have, never will!"

"There's a first time for everything, toots."

"Toots?! How dare you call me Toots! YOU WILL REGRET THAT! ALL THE WAY TO THE GRAVE!" Me-Mow calmed down, and smiled. "Then again, there is no afterlife for robots, is there? Will you even have your own grave? Or will your parts just be thrown away, like you don't have a soul. Oh, wait, you don't!" She started laughing.

Beemo balled his fists. "Big mistake." Beemo said. He then pointed at her. "Get her, NEPTR!"

NEPTR started using his microwave to launch pies at Me-Mow. However, the tiny cat assassin swiftly dodged every one. Me-Mow then climbed up a tree branch, where Beemo and NEPTR couldn't get her.

"Come and get me, boys," she called out. "Unless you're scared."

Beemo went up the ladder to catch Me-Mow, but NEPTR stayed put.

"Why aren't you coming?" Beemo asked.

"I have tank treads for feet, and one arm, that's not even an arm, it's just a claw," NEPTR said in a sarcastic voice. "I'm the champion ladder climber! I've won every medal in the sport!"

"Now's not the time for sarcasm," Beemo said. Beemo then started to climb up ladder after ladder to get to Me-Mow, and finally found her.

"Now you're all alone," said Me-Mow. "And unarmed. How foolish."

"You don't have a weapon, either," Beemo responded.

"Don't I?" she asked. Me-Mow then pulled out another dagger from her mouth, and this dagger was unique, for it was made out of darkness. "Prepare to die!"

Me-Mow rushed Beemo again, and then stabbed Beemo in his control pad with the dagger. This time, the dagger went through Beemo's mechanical body. Beemo moaned in pain, and got down on his knees.

"Believe I'm dangerous now?" Me-Mow asked.

"Go...jump...into...a...saucer...of...milk!" Beemo said, still writhing in pain. Beemo then fainted. Me-Mow laughed in amusement.

"This was the easiest job ever!" she said to herself. "Not even a challenge. Now, to collect my prize!" Me-Mow left the Tree Fort, laughing in a sinister voice.

* * *

In what was an hour later, Beemo awoke to find himself surrounded by cops (cats).

"Officer Davis?" he asked. "Where's Officer Davis?"

One cat walked up to Beemo.

"What do you need?" Davis asked.

"What happened to me?" Beemo asked. "The last thing I remember is that tiny cat assassin stabbing me, and then I blanked."

"The assassin left, thinking you were dead," Davis began. "NEPTR alerted us of an assassin in the Tree Fort, so we tried to find you and the assassin, but she escaped, and we found your unconcious body on a tree branch. Luckily, we managed to revive you, just before you died. Also, NEPTR told us everything. What happened to Finn and Jake, the five people searching for their murderer, and your plan to find them."

"Let me guess," Beemo said. "You're going to lock me and NEPTR up until the case is closed."

"No. We are granting you permission to leave and avenge the great Finn and Jake. We will stay and guard the Tree Fort. Also, we are sending a squad to hunt down the assassin."

"Call off your squad. I'll take down the assassin."

"I thought you were going to tell the five they were on a wild goose chase."

"That can wait. First, I'll take NEPTR with me to hunt down that dirtbag assassin." Beemo balled his fists. "I've got a score to settle with her."


	8. Chapter 8: NEPTR's Turn

**Adventure Time and Regular Show Xover Extravaganza!**

**By: ITM**

_(Note: I don't own AT or RS, I'm just sharing my writing talents with the website.)_

**Chapter 8: NEPTR's Turn**

After recovering in the Tree Fort, Beemo, along with NEPTR, set out to find Me-Mow.

_"That cat's gonna wish it was never born!" Beemo thought._

* * *

Meanwhile, back at the G.O.A. hut, Kanzargon (in his old man form) was talking to Me-Mow in her room.

"Did you make sure that the robot died?" Kanzargon asked.

"Trust me," Me-Mow stated. "No one could've survived a stab in the heart."

"You idiot!" Kanzargon yelled. "Robots don't have hearts! I want proof the robot died! Go and bring back the body of the robot!"

"Hey!" Me-Mow yelled back. "The agreement was that once the robot was downed, I got paid! So fork over the money!"

Kanzargon pulled out an axe made of darkness from his robe. He raised it, about to chop Me-Mow into super-bite-size pieces. "The deal has changed. Get with the program!"

"Ahhhhh! Okay! I'll bring back the body!"

Kanzargon put the axe back in his robe. "Much better."

Me-Mow quickly scurried out her window and towards the Tree Fort again, faster than the first time she went there.

* * *

Beemo and NEPTR were traveling towards the one place where they were sure to find Me-Mow: the G.O.A. hut, However, very few would dare to travel to a hut filled with trained assassins, ready to cut you down in two seconds on one command. But, Beemo had a big grudge with Me-Mow, ever since the stabbing.

"That freak feline has to be around here somewhere," Beemo said.

"Maybe my sensors can pick up her location," NEPTR suggested.

"Good idea," Beemo said.

NEPTR spun around on his tank treads multiple times, and then pointed his claw in a certain direction.

"I've sensed the cat's presence," NEPTR began. "One mile in that direction."

"Gotcha, cat!" Beemo said. The two went off in the direction Me-Mow was located.

* * *

Meanwhile, with the five searching for Nograznak, their efforts seem to be in vain.

"Its been a day now," Ice King whined. "And we searched all the west side of Ooo. We can't find Nograznak!"

"Don't be a weenie," Marceline said. Saying the word "weenie" reminded Marceline of Finn and Jake. "Let's search the east side!" Everyone nodded in agreement, except Ice King, who just nodded reluctantly. The five went off towards the east side of Ooo.

* * *

Back with Beemo and NEPTR, the robot duo were still traveling towards Me-Mow, but NEPTR noticed something strange in his sensors.

"Hmmm," NEPTR muttered.

"What is it?" Beemo asked.

"It seems that we're traveling one mile faster than I calculated," NEPTR began. "Apparently, we seem to be coming very close to Me-Mow, and sometimes, we're getting closer to her when we're not even moving!"

"What are you saying?" Beemo asked.

"Either we are moving at an unreal speed," NEPTR answered. "Or, Me-Mow is coming to us."

As soon as NEPTR finished his sentence, Me-Mow came speeding by on all fours. She stopped when she saw Beemo and NEPTR.

"Well, well, well," Me-Mow said. "I guess that old man was right. You are still alive. Or did you die, and you were rebuilt?"

Beemo balled his fists, but kept his cool. "Big words coming from a failure assassin," he said with a smirk.

"Big words coming from a guy with buttons on his chest," Me-Mow retorted.

"Enough!" NEPTR yelled. "I'm going to take you down, cat!"

"No, NEPTR," Beemo said. "The cat's mine!"

"I'll take on both of you right now, if it'll shut you two up," Me-Mow challenged.

"No, you're gonna fight me," Beemo said in a stern voice.

"Beemo," NEPTR said. "You've already gotten a chance to fight Me-Mow. I want a turn. Trust me, I can beat him. After all, a partnership is based around trust."

Beemo then hesitated after hearing what NEPTR said. "Trust" was a thing that Beemo has never relied on before, but Beemo thought: what was more important? Fighting a cat? Or avenging Finn and Jake? Obviously, Beemo chose choice #2.

"Alright, NEPTR," Beemo agreed. "You can fight her. But, be sure to give her a good pounding for me."

NEPTR smiled after hearing that. NEPTR drove over to face Me-Mow.

"You're an even bigger junkpile than that other robot!" Me-Mow laughed at NEPTR. "It looks like you were slapped together with a bunch of spare junkyard parts."

"Aren't you the pot calling the kettle black," NEPTR retorted.

Me-Mow scowled and bared her fangs. "HOW DARE YOU INSULT ME AND MY FAMILY!" Me-Mow screamed. "I'LL KILL YOU!"

Me-Mow rushed NEPTR, but NEPTR launched a steaming hot pie at Me-Mow, and the pie hit its target. Me-Mow was stopped in her tracks, covered in pie filling. Me-Mow was scurring all over the place, her tiny body burning from touching the hot pie.

"Looks like giving you a chance turned out to be a good idea," Beemo said, laughing at Me-Mow's pain. "This is a laugh riot!"

Me-Mow shook off the pie filling and frowned at Beemo.

"I am not defeated yet!" Me-Mow exclaimed, facing Beemo. "I still have my trump card!" Me-Mow reached into her mouth and pulled out the dagger made of darkness. "Remember this, Beemo? It's the very same dagger that put you out of action!"

Beemo simply smiled a cocky smile and said, "If I were you, I wouldn't take my eyes off the robot that can chuck pies at amazing rates!"

Me-Mow turned to face NEPTR, only to get blasted with another hot pie. And another. And another. And another. And another. NEPTR was launching pies directly at Me-Mow, each one not missing its target. Me-Mow was now starting to suffocate under all of the pies she was buried under.

"Don't let up for a second, partner!" Beemo said to NEPTR. Hearing the word "partner" come out of Beemo's mouth made NEPTR very happy. In fact, upon hearing that, NEPTR started launching pies at a faster rate than before. All NEPTR ever wanted was friends, and hearing the word "partner" come out of Beemo's mouth made him realize that Beemo was his best friend, next to his creator, of course.

"Blargh," Me-Mow choked out. She couldn't take anymore pies blocking her oxygen supply, and finally suffocated under all of the pies. NEPTR stopped hurling pies.

"My life sensors have stopped sensing the cat's life force," NEPTR exclaimed. NEPTR drove over to the small hill of pies, and started to sift through the pies with his claw. He finally found Me-Mow under all the pies, and saw that she stopped breathing.

"Yup, she's dead," NEPTR announced.

"Hooray!" Beemo chanted in happiness. "High-five!"

NEPTR drove over to Beemo and high-fived his hand with his claw. Beemo looked over at Me-Mow's dead body.

"Well, Me-Mow," he said with a smirk. "Looks like _you_ are the best thing to put into a pie." Both Beemo and NEPTR laughed. Finally, they had beaten Me-Mow.

* * *

Meanwhile, back in Kanzargon's dark realm, he was watching the fight between Me-Mow and Beemo and NEPTR.

"Pathetic cat!" Kanzargon yelled. "Now I have one less minion, a Hero of the Prophecy is still alive, and I lost a dagger! This is just great! I don't want to have to bring my star player back into this game, but I will, if my next minion fails me."

Kanzargon opened another portal and transformed into his old man form. He stepped into the portal and was whisked away back to Ooo.


	9. Chapter 9: The Longest Chapter Yet!

**Adventure Time and Regular Show Xover Extravaganza!**

**By: ITM**

_(Note: I don't own AT or RS, I'm just sharing my writing talents with the website.)_

**Chapter 9: The Longest Chapter Yet!**

**We now head back down to the Underworld, where Finn and Rigby have to find Death's castle.**

"I thought you knew the way to Death's castle?!" Rigby screamed, spazing out.

"I found it by accident," Finn explained. "You see, there were skeletons chasing Jake and I the first time we came here, trying to eat our flesh, and while we were running, we stumbled upon Death's castle. But we can still find it! It's made out of light, so we can't miss it!"

"I guess," Rigby said, calming down. "But what if the skeletons that chased you before chase us?"

"They won't," Finn said. "We're dead. We have no flesh!"

"That isn't very comforting."

"Look, we'll just walk around, ask some locals, and then we're bound to find it eventually."

"Alright then! Let's go!"

Just like that, the two spirits became friends, and set off in search of Death's castle.

* * *

Meanwhile, back at the Park, Mordecai and Rigby's dead bodies were loaded up in coffins, and buried in the old cemetery. Lots of people were there, especially Margaret and Eileen. After the funeral, the two cried over their friend's graves.

"Mordecai!" Margaret cried. "I'm sorry for never telling you my true feelings for you! I guess it's too late now!" Margaret cried in her hands.

"Rigby!" Eileen cried. "I've always loved you! But, I never knew if you loved me back!" Eileen cried in her hands, too.

Far behind the two girls, Benson, Skips, Pops, Muscle Man, High-Five Ghost, and Thomas were all sad. Benson turned his head away from Mordecai and Rigby's graves out of shame. Skips just closed his eyes and tuned away. Pops was on the ground crying. Muscle Man, High-Five Ghost, and Thomas all looked down at the ground in depression. A police officer came by and asked Benson some questions.

"Did you see the killer?" the police officer asked.

"No," Benson answered. "I just walked outside, and found the two of them on the ground dead."

"Well," the police officer started. "Amazingly, after examination, there were no fingerprints or any sort of forensics on the bodies or near the crime scene. I'm afraid this killer must be an expert assassin of some sort, for he or she left no trace behind."

"How is that possible?" Muscle Man asked.

"I don't know,' the police officer answered. "But, we'll do our best to find the killer. However, if the culprit is not found within a week, the killer is most likely out of the city, the state, or even out of the country." And with that, the police officer left.

"I guess we have to get back to work," Skips said.

"No," Benson said. "Everyone is given the day off today for the funeral. We resume work tomarrow."

Everyone nodded, and left to their respective homes. Maargaret and Eileen were still crying over Mordecai and Rigby's graves. However, they had to leave when the park closed for the day. It was a dreary day, indeed. But, little did everyone in the park know, was that Rigby was on his way back, and with a new buddy.

* * *

Meanwhile, back in Ooo, Beemo and NEPTR had just gotten back to the Tree Fort, where they met up with Officer Davis.

"Welcome back," Davis said with a grin. "Since you're back in one piece, I take it that you beat the assassin?"

"Yup," Beemo replied. "Me-Mow the assassin has been killed. We won't have to worry about her anymore."

"Good," Davis said. "I guess it was a good idea to send you out to find the assassin instead of my squad."

"Now that the assassin is out of the way," NEPTR said. "We can go track down the five."

"Alright," Davis said. "But it's dangerous out there, you'll need to be armed. Come with me."

Officer Davis led the robot duo into the treasure room.

"Grab a weapon from the treasure pile," Davis suggested. "It'll help you on your journey."

Beemo looked around for a weapon, but all the weapons were too big for him and NEPTR. However, Beemo noticed a dagger among a pile of gold coins. Beemo picked up the dagger and swung it around like a sword. Beemo smiled and put the dagger in a compartent on his side. "This'll do."

"I don't need a weapon," NEPTR said. "I am a weapon!"

"Then I guess that settles it," Davis announced. "Good luck on your journey."

"Thanks!" both Beemo and NEPTR called out as they headed out the door and to the Candy Kingdom. Their journey would be hard, perilous, and full of evil guys. But they were two robots on a mission. A mission to avenge their friends.

* * *

Meanwhile, the five had just finished searching the east side of Ooo. Still no sign of Nograznak.

"This is bunkrolls!" Ice King whined. "We searched the west and east side of Ooo, and still no Nograznak! Maybe he's on another planet, or something. He's sure not here! Let's just give up!"

"Shut up!" Flame Princess said. "You've been whining ever since we checked the west side. Maybe if you shut your mouth for five minutes, we'd get something accomplished!" She was very annoyed with the Ice King for saying "let's give up." She wasn't about to give up on Finn.

"Let's head back to the Candy Kingdom to get a map of Ooo," Bubblegum said. "Maybe a map will give us better guidence."

"Good idea," Marceline said. "Let's go to the Candy Kingdom!" The five flew off to the Candy Kingdom. Unbeknownst to our friends Beemo and NEPTR, if they'd hurry, they'd be able to catch the five.

* * *

Meanwhile, back at the Underworld, Finn and Rigby had been asking the locals around if they knew where Death's castle was. Luckily, one of the locals pointed the way out for Finn and Rigby to Death's castle. Soon enough, they had finally made it to the gates of the castle.

"Finally!" Rigby said with excitement. "We did it!"

"Yeah!" Finn said as he pounded fists with Rigby. "You know, it's funny. I've never seen you around Ooo before."

"Ooo?" Rigby said in confusion. "What the heck is Ooo? Is that a foreign country? 'Cause if it is, that would be strange, considering how American you look."

"American?" Finn said in confusion. "What the jerp is American? Is that another planet?"

"Americans are citizens of America."

"What's America?"

"It's a country."

"What's a country?"

"You don't know what a country is?"

"No. Is that a term for something?"

"A country is a big piece of land seperated from other countries."

"There's more than one country?"

"I thought you didn't know what a country is."

"What's a country?"

Rigby did a facepalm. "Look, there are, I don't know, at least 100 countries on Earth, I think. Do you know what Earth is?"

"Sure. Earth is the planet we live on."

"Good. Kid's not as dull as I thought."

"Can we just go inside now?"

"Sure."

Before they went inside, Finn gasped. "Jake! I forgot about Jake! He needs to come back with us!"

Rigby gasped as well. "Mordecai! I forgot about Mordecai! We need to find him!"

Suddenly, the most incredible thing happened. Finn and Rigby sensed with their new spirit forms the presence of two other spirits behind them. They both and turned around, and their jaws dropped. It was Jake and Mordecai in spirit form.

"Hey, guys," both Jake and Mordecai said with a smile.

"Jake!" Finn yelled.

"Mordecai!" Rigby yelled. Each pair of best friends went over to each other and hugged each other. Normally, Mordecai and Rigby would not want to hug, but they finally realized how important their friendship was.

"How did you guys get here?!" Finn and Rigby asked.

"Welp," Jake started. "It's a long story. Which is why I'm gonna put in sequential order! First, I found out I was in the Underworld. Second, I met Mordecai here, and we decided to make our way to Death's castle to bring us back to life, so we can get revenge on that jerk Nograznak. Third, we asked the local skeletons and spirits where Death's castle was, and one skeleton pointed the way out. Finally, we came and saw you guys beat us here already, which was a good thing, too. We almost forgot about you guys."

"So this is Finn," Mordecai said, eyeing the human boy. "He's a kid."

"And this is Mordecai," Finn said, eyeing him back. "He's a blue jay."

"This must be Rigby," Jake said, staring at Rigby. "He's a raccoon. Which is strange, because he's brown."

"This guy is Jake, huh?" Rigby said, staring at Jake. "He's a dog. Which is strange, because he's orange."

For a few moments, there was silence. Then, each person shook hands with the person they were looking at and said, "Nice to meet you!"

* * *

Meanwhile, back in Ooo, Kanzargon, in his old man form, headed back to the G.O.A. hut. He met with the same lizard guard he saw before, and started to talk to him.

"I would like to complain," Kanzargon said.

"About what?" the lizard asked.

"Your assassin Me-Mow was a failure!" Kanzargon complained as he reached into his robe and pulled out the dead cat, dangling her by her tail. "I want a better assassin to hire! Maybe one that is first-class!"

"Very well," the lizard said. "Come inside. But first..." The lizard stretched its tongue out at Me-Mow's dead body, and ate it. "Good eatin', right there."

After finishing his little snack, the lizard led Kanzargon into the hut. He pointed at a bulletin board on the wall.

"On that board," the lizard began. "Is a list of every assassin we have. Oops, I forgot." The lizard pulled out a pen from his pocket and crossed off Me-Mow's name. The lizard then put the pen back in his pocket. "Pick any name on the board that's not crossed off."

Kanzargon looked at the board and put his finger on his chin. "I really need an assassin that's around, yay tall." Kanzargon made a gesture with his hands to show the aproximate size of the assassin he needed. Strangely, the size Kanzargon was suggesting was about the size of a small robot.

"Hmmmm," the lizard muttered. "I would reccomend Rix."

"Sounds great," Kanzargon said with a smile.

"I'll go get him," the lizard said. A few minutes later, the lizard came back with a small-robot sized assassin. Rix was an olive-colored goblin with a small spear sheathed in a sheath on his back. Rix had fangs, claws, and a tail with a couple spikes on the end of it. Kanzargon thought he was the perfect match for Beemo and his friend known as NEPTR.

"Perfect!" Kanargon exclaimed. He pulled out a sack of gold from his robe and waved it in front of Rix. "This is yours if you can assassinate my target."

"That depends," Rix questioned. Rix had an evil, hunt-for-fun kind of voice. "Who's the target?"

Kanzargon put his sack of gold back in his robe and pulled out an orb. Kanzargon rubbed the orb, and the orb showed Beemo and NEPTR heading towards the Candy Kingdom. Kanzargon pointed at Beemo.

"This robot is your target," Kanzargon instructed. 'Do what you want with the other robot. I could care less. Just make sure that this robot dies!"

"Understood," Rix replied. After that, Rix headed out of the hut, and in search of the robot. Kanzargon left the hut as well, only to go back to his realm.

"That goblin better succeed," Kanzargon said to himself before he left Ooo. "Or else I'll have to bring back my #1 assassin." And with that, Kanzargon went through the portal back to his realm.


	10. Chapter 10: Comeback!

**Adventure Time and Regular Show Xover Extravaganza!**

**By: ITM**

_(Note: I don't own AT or RS, I'm just sharing my writing talents with the website.)_

**Chapter 10: Comeback!**

_"I have returned! The Lord Of Dimensions has returned to set order to the Multiverse, but to do that, I must travel to the Ooo Dimension and warn a few of the 10 Heroes of the Prophecy of the coming danger that threatens the Multiverse! Until then..."_

**We now shift back to the Underworld, where our four little spirit friends have finally made it to Death's castle.**

Finally, Finn, Jake, Mordecai, and Rigby have made it to the entrance of Death's castle. They knocked on the door, and sure enough, Death opened it.

"You guys again!" Death exclaimed, recognizing Finn and Jake. "I thought you guys left! And you guys died?!"

"Hey," Rigby said. "You're not the Death we know!"

"Yeah!" Mordecai agreed. "The Death we know has a leather jacket, hair, a scythe, and a motorbike!"

"Oh, that Death?" Death said. "I'm playing poker with him inside now!"

Mordecai and Rigby looked in and saw the Death they knew sitting down at a poker table. They also saw his motorbike parked inside.

(Author's Note: To differentiate both Death's, I will label them like this:

Adventure Time Death: AT Death

Regular Show Death: RS Death

Remember that, now.)

"Oi, Mordo and Riggs," RS Death called out. "What're you doin' 'ere?"

"Wait," AT Death said, facing RS Death. "You know these guys? Well, any friend of his is a friend of mine! Come on in, all four of you!" AT Death let the four spirits in. RS Death frowned when he saw Mordecai and Rigby.

"You guys died?!" he yelled. "But you two were gonna die of 'art attacks!"

_"Huh," Mordecai thought. "To think, after all we've been through, and going to be in, we die of heart attacks. Go figure."_

"We got killed by some weird shadow guy named Nograznak," Rigby told RS Death.

"Yeah," Finn added. "Us, too."

"Wait," Jake interrupted. "How can there be two Deaths?"

"Oi, I come from a different dimension," RS Death told Jake.

"Another dimension?" Finn asked.

"Yeah," AT Death said, pointing at RS Death. "He is the Death of the Park Dimension."

"Park Dimension?" Mordecai asked.

"Yeah," RS Death told Mordecai and Rigby. "It's where we're from. The really strange thing is that I've never seen these two boys before." RS Death pointed at Finn and Jake.

"That's because they're from the Ooo Dimension," AT Death told RS Death.

"No wonder I 'aven't seen them before," RS Death said.

"Wait a minute," Finn and Jake said. "If you guys aren't from Ooo..."

"And if you guys aren't from the Park Dimension..." Mordecai and Rigby said.

Suddenly, the pieces were put together, and the truth was revealed.

"YOU GUYS ARE FROM ANOTHER DIMENSION!" the four of them all screamed.

* * *

Meanwhile, back with Beemo and NEPTR, the robot duo were on their way to the Candy Kingdom.

"If we can ask Peppermint Butler for the location of the five," Beemo explained. "We can find them and tell them this was all a big waste of time."

"Right!" NEPTR agreed. "Then, we'll ask poppy (Ice King) if he has any mystical items that can help us locate Nograznak!"

"Exactly!" Beemo said. "Then finally, the seven of us we'll take Nograznak down!"

(Author's Note: That was Beemo and NEPTR's entire plan in a nutshell. If you guessed it right, give yourself a pat on the back. If you didn't, well, go drown your sorrow in a tub of ice cream. Love you guys!)

After half an hour of running, the robot duo finally made it to the Candy Kingdom. They entered and started running towards the castle.

"We're almost there!" Beemo said excitingly.

"Yeah!" NEPTR said in a cheerful voice. "Nothing can stop us now!"

Suddenly, Beemo stopped running, and slapped his hand on his screen.

"Nice going, brainiac," Beemo said in an annoyed voice.

NEPTR stopped moving and drove towards Beemo. "What's that supposed to mean?" NEPTR asked.

"You know what you did!" Beemo shouted at him. Then, he started talking in NEPTR's voice. "Nothing can stop us now!" Beemo switched back to his regular voice. "You don't say things like that! Don't you know that Glob is always watching, waiting for someone to say something like that, and then gives them something that stops them!"

Suddenly, a small figure came out of a dark alley. Beemo and NEPTR turned to face the figure, and saw that is was a goblin their size. The goblin unsheathed a spear he had in a sheath on his back.

"'Sup?" the goblin asked. "I'm here to kill you guys."

"See?! See?!" Beemo shouted. "I told you!"

NEPTR ignored Beemo and stared at the goblin.

"Who are you?" NEPTR asked.

"The name's Rix," the goblin answered. "Assassin, second class."

"Oh, great," Beemo started. "ANOTHER assassin."

"You picked the wrong time to assassinate us!" NEPTR said boldly. "There are hundreds of Banana Guards in the Candy Kingdom. Once they see you attacking us, they'll lock you up in a dungeon immediately! I suggest you leave now, unless you want to spend the rest of your days in a cold dungeon!"

"You wanna know what my response to that is?" Rix asked. "I'm gonna kill you. Short and sweet."

Just like that, Rix rushed NEPTR and stabbed him with his spear. The spear went right through the glass of his microwave.

"NEPTR!" Beemo yelled. "Banana Guards! Come quick! There's an assassin here!"

"Man, shut your mouth, fool!" Rix pulled his spear out from NEPTR and threw it at Beemo. Beemo saw the incoming spear and dodged it. Rix then pulled out a little dagger from his pocket and held it up to NEPTR. "Call for the cops one more time, and this chump's gonna have a heaping help of dagger-in-the-face, with a big serving of vitamin death! With a side of broken robot parts, and..."

"I get it! You're the funny guy!" Beemo stated.

* * *

Meanwhile, back in the Underworld, Finn, Jake, Mordecai, and Rigby have still not gotten over the fact that they're from different dimensions.

"YOU'RE FROM ANOTHER DIMENSION!" Finn and Jake yelled. "HOLY SLUG!"

"YOU'RE FROM ANOTHER DIMENSION!" Mordecai and Rigby yelled. "HOLY CRAP!"

"They've been like this for an hour," AT Death said to RS Death.

"I know," RS Death said. "It's gettin' annoyin'."

* * *

Meanwhile, back with the five, they're just moments away from entering the Candy Kingdom.

"Here we are," Bubblegum said. "Let's get that map!"

"Wait," Ice King said. "Listen." The five stopped and listened for a second. "I think I heard Beemo cry for a banana!"

"Why would Beemo cry for a banana here?" Marceline asked.

"He must be yelling for a Banana Guard!" Bubblegum explained. "He must be in trouble!"

"Let's go help him!" Flame Princess yelled. The five of them flew down to the Candy Kingdom to find Beemo.

Meanwhile, just a few yards away, Rix was threatening Beemo.

"I'm warning you!" Rix warned. "Don't you dare call for help again! Or your friend here is gonna get got!"

Beemo was in a corner. (Metaphorically speaking.) He didn't know what to do. This assassin was much more skillful than Me-Mow, that' for sure. If he called for help, NEPTR would die. If he didn't, he and NEPTR would probably die. NEPTR was already badly wounded from that spear impalement. If NEPTR took one more severe wound like that again, NEPTR would surely die. And just like Me-Mow said: there is no afterlife for robots. Beemo had no choice but to fight. Beemo opened a compartment on his body and pulled out his dagger. Beemo readied in a battle stance, and gestured for Rix to come here and fight. Rix smiled at that gesture and walked away from NEPTR and towards Beemo.

"You got guts," Rix stated. "It's too bad you'll never be able to use them again after I'm through with ya!"

"Joke's on you," Beemo said with a smirk. "Robots don't have guts, or organs for that matter."

"I'm gonna kill you, now," Rix said as rushed towards Beemo. The two clashed daggers. Beemo swung his dagger at Rix, but missed. Rix then tried to stab Beemo, but Beemo jumped out of the way. Beemo was scowling at Rix.

"I won't back down!" Beemo yelled.

"Good," Marceline said. "No one wanted you to."

Rix looked behind him and saw a vampire, a fire elemental, an ice elemental, a rainicorn, and a girl made of bubblegum standing over him.

"As princess of the Candy Kingdom," Bubblegum started. "I hereby place you in the dungeon for thirty years!"

"Ain't nobody got time for dungeons!" Rix stated as he then ran back into the dark alley where he came from, picking up his spear along the way. "I'll be back, robot!" Rix yelled. Bubblegum ran towards Rix, but lost him after he went into the alley.

"He's gone," Bubblegum said.

Beemo ran over to NEPTR.

"NEPTR!" Beemo said in a worried tone. "Are you okay?"

"I'm fine," NEPTR said. "Just one hole through my glass."

"That's good to hear," a familiar voice said. Upon hearing that voice, all seven of them gasped.

"No way!" Beemo said.

"It couldn't be!" Lady Ranicorn said.

"It can't be!" Marceline said.

"Impossible!" Flame Princess said.

"Unthinkable!" NEPTR said.

"Unimaginable!" Ice King said.

"It defies all logic!" Bubblegum said.

All seven of turned and saw Finn and Jake standing right behind them!

"FINN! JAKE!" they all yelled. Everyone ran over to hug Finn and Jake, even Flame Princess, but nobody cared about the burning heat. They were glad Finn and Jake are somehow back.

"I missed you, creator!" NEPTR said.

"I missed you, guys!" Beemo said.

"I missed you, Finn!" Flame Princess said.

"I missed you, Jake!" Lady Rainicorn said.

"I missed you, bros!" Ice King said.

"I missed you, weenies!" Marceline said.

"I missed you, Finn and Jake!" Bubblegum said.

Everyone stopped hugging and suddenly all started wondering something.

"How are you guys alive?!" they all asked.

"Well, it goes like this," Jake explained. "We met up with Death in the Underworld, explained the situation with him, he returned our souls, and he teleported us back to Ooo."

"Oh, and one more thing," Finn added. "We met two really cool guys who were also killed by Nograznak, and they agreed to be sent here with us. So, everyone, we want you to meet our new friends Mordecai and Rigby!"

A blue jay and a raccoon walked out from an alley, and both started beat-boxing.

"My name is Rigby!"

"And my name's Mordecai!"

"We're both two bros and we love us some apple pie!"

The seven of them stared at Mordecai and Rigby very confusingly.

"Yeah, we didn't have much time to think of something clever."

* * *

Meanwhile, back in Kanzargon's dark realm, Kanzargon was watching Rix flee from the five people who towered over him on his orb. What he saw next made him go ballistic. He saw Finn, Jake, Mordecai, and Rigby alive.

"WHAT?!" Kanzargon screamed. "THEY'RE SUPPOSED TO BE DEAD! I SAW THEM DIE WITH MY OWN EYES! ARGHHHHHHHHHHHHH! FINE! I DON'T KNOW HOW THEY'RE STILL ALIVE, BUT I'LL GO OVER THERE AND KILL THEM MYSELF!" With that, Kanzargon opened a portal to Ooo and went in it.

* * *

Back at the Candy Kingdom, Finn, Jake, Mordecai, and Rigby explained everything to the seven, and then the seven explained what they did while they were dead.

"So Me-Mow came back and tried to kill Beemo and NEPTR?" Finn asked. "But she's dead, now?"

"And the five of you tried to hunt down Nograznak to avenge us?" Jake asked.

"And an assassin named Rix tried to kill you two robots?" Rigby asked.

"Yes," they all answered.

"And when you guys were done yelling about the fact that the bird and the raccoon were from different dimensions, the four of you were brought back to life by both Deaths, and sent here?" Beemo asked.

"Then Mordecai here dug up Finn's body, and Rigby dug up Jake's so they wouldn't suffocate?"

"Yup," the four newly revived heroes answered.

"So that's how you came back," a dark voice echoed.

Everyone gasped. Suddenly, a portal opened up in the suddenly blackened sky, and a shadow thing came out of it. It was hovering in the air.

"I am Kanzargon, the Lord of Space," Kanzargon said.

Finn and Jake gasped. "You're the father of Nograznak!" they both yelled. everyone else gasped upon hearing that.

"Wait a second," Bubblegum said. "Nograznak is Kanzargon spelled backwards! He is the father!"

"Huh," Beemo said. "I was way off."

"What do you want, you jerk!" Rigby yelled.

"I'm here to kill you guys once and for all!" Kanzargon yelled.

"Not a chance!" Marceline yelled back. "You can't fight all 11 of us!"

"I don't want to fight _all_ of you, just the human, the dog, the blue jay, and the raccoon!" Kanzargon said. The four of them gulped.

Suddenly, Kanzargon started to generate a ball of dark magic and dark lightning between his hands. He threw it at Finn, Jake, Mordecai, and Rigby, and it hit them right on target.

"This spell will be your end!" Kanzargon laughed in an evil voice.

"NOOOOOOOOOO!" the other seven yelled, as they stood in one place petrified in fear.

Finn, Jake, Mordecai, and Rigby all screamed for their lives as they suddenly vanished. Kanzargon laughed and went back through the portal. As soon as he left, the sky turned back to normal. The seven remaining people were left there, standing in complete shock and fear from what just happened. They all then screamed.

"NOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOO!"

* * *

Suddenly, Finn, Jake, Mordecai, and Rigby woke up and saw that they were outside a green house, grass all around them, and blue skies.

"Oh, phew," Finn said, but strangely with Mordecai's voice.. "We're at the Park. Which means we're still alive!" Finn looked over at Mordecai, but saw Mordecai's body in front of him. "Hey, what am I doing over there?"

"I don't know," Jake said with Rigby's voice.

"Why do you have my body?" Rigby asked with Jake's voice.

"Why does he have my body?" Mordecai asked with Finn's voice.

Everyone looked at each other and gasped.

"Are we in your bodies?" Finn and Jake asked Mordecai and Rigby.

"Are we in your bodies?" Mordecai and Rigby asked Finn and Jake.

Suddenly, they all screamed.

"AHHHHHHHHHHHHHHHHHHHHHHHHHHH!"

* * *

**Finally finished! What will happen next? How did our heroes switch bodies? What about Rix? Is Kanzargon's evil reign of terror ever going to end? Find out (or not) in: "Adventure Time and Regular Show Xover Extravaganza 2: Cliche Chaos!"**


End file.
